Power unit for amusement devices and the like



April 16, 1946.

c. E. SHORT ET AL POWER UNITS FOR AMUSEMENT DEVICES AND THE LIKE FiledMay 15, 1945 '2 Sheets-Sheet l INVENTORS f EBY;

ATTORNEY V 0 2 9 7 H F. E W m2 fl f/ m E: 1 Wu F mmz r 1 a April 1946. vc. E. SHORT ET AL I 2,398,471

POWER UNITS FOR AMUSEMENT DEVICES AND THE LIKE Filed May 15, 1945 2Sheets-Sheet 2 1 FIGURE 4 WYSM IN VEN TORS ATTORNEY Q Patented Apr.16,1946 A PATENT FFICE POWER FOR AMUSEMENT DEVICES AND THE LIKE CharlesElliott Short and Edward Madison Brown, Jr., Wilmington, DeL; said Brownassignor to said Short Application May 15,

2 Claims.

This invention relates to a power unit for amusement devices, toys, andthe like and means to actuate the same.

Moving toys, and thelike, are usually equipped with motive power in theform of electrical, spring operated or gravity operated motors. Theserequire a spring, a battery, or hand resetting. Spring orgravity-operated toysoperate for only a short period of time beforerequiring re-setting. Battery-operated toys are expensive to operate.

The object of this invention is a device, operated solely by the heat ofthe surroundings, which is entirelyself-contained and requires noadjustment, operates with greater force and reliability than thoseheretofore known, over long periods of time, and requires no resetting,rewinding, or

battery. I

Our invention may be utilized for operating all sorts of light powerdevices, where reliable movement, not requiring manual attention, isneeded. An example of our inventiongis shown in Figures 1 to 4 of theaccompanying drawings, although we do not limit ourselves to theparticular form there shown.

Broadly, our invention comprises the provision of a supply of a volatileliquid, a vapor space above said liquid, into which vapor space heatflows from the surroundings, acting to expand said vapor, a tubereaching nearly, but not quite, to the bottom of the pool or liquid, upwhich tube the liquid in the pool is forced, to flow into an upperchamber which is cooled, for example by evaporation of water or otherliquid. As the liquid fills the upper, cooled chamber, the balance ofthe device, resting upon hinges or pins, for

example, is altered by the weight of the liquid in the upper chamber,and the device as a whole tilts on the hinges or pins, thus uncoveringthe bottom of said upright tube and allowing the liquid in the upperpart of the device to flow back down the upright tube to the lower partof the device, whereupon the cycle is repeated.

In the accompanying drawings,

Figure 1 represents one embodiment of our invention, in the shape ofabird resting upon a wire support, the latter being fastened to the rimof a vessel containing water. Normally, the bird remains upright, atfirst, then gradually leans over toward the water in the vessel, finallydipping its beak into the water, then almost immediately resumes theupright position. This cycle is repeated every few seconds, constantlyand reliably.

Figure 2 represents a vertical section of the 1945, Serial No. 593,836

, device of Figure l in the upright position. Figure 3' represents avertical section of the same device as it begins to tilt forward, andFigure 4 is a vertical section of the device as the liquid 5 hasreturned to the lower chamber of the device and the device is about tore-assume the upright position shown in Figures 1 and 2.

In the device according to our invention we allow .heat from thesurroundings to pass into the body of thedevice and expand the vaportherein, to cause a slightly elevated pressure. This pressure acts uponthe liquid beneath said vapor, forcing theliquid upward, through thecentral tube shown, into the upper'chamber. The

upper chamber is maintained at a slightly lower temperature than thelower chamber, so that the pressure in the upper chamber is slightlyless,

back to the upright position, whereupon the cycle is repeated.

As means for reducing the temperature of the upper chamber below thetemperaturev of the lower chamber we utilize the heat removed byevaporation of water or other volatile liquid from an absorbent materialattached to the upper chamber.

As material of construction of our device we 'may use, for example, amaterial not attacked or dissolved by volatile liquids, such as glass orsheet metal, but we'prefer glass for strength and ease of tight sealing.Where other shapes or 40 designs of toys and the like are desired, wemay construct the operating means of glass and enclose the same,exceptfor the cooling means, in

stamped or shaped metal casings.

. We find it advantageous or necessary, depending upon the liquid weemploy in our device. to

exhaust most of the air from our device, so that the vapor therein willnot be diluted by fixed gases.

As liquid in our device we preferably use a volatile liquid, such asmethyl alcohol, ethyl alcohol, ethyl ether, acetone, chloroform,methylene chloride, or thelike. After placing the desired quantity ofvolatile liquid in the device, we exhaust the air remaining in thedevice through a tube still attached to the device, then seal on.

absorbent material'i. v

balanced by the weight of liquid in upper chammally wet with water orother volatile liquid and from which the water or other volatile liquidevaporates.

In the vertical section, Figure 2, 6 represents the volatile liquidcontained in the device, 1 the volatile liquid vapor above said liquid,8 the lower chamber of the device, 9 the upper chamber of the device,sealed ofl from said lower ch mber at the neck l0, except throughupright be H, which reaches nearly to chamber 8.

In the vertical section, Figure 3, heat from the surroundings/hasentered lower chamber 8, expanded vapor I therein and caused said vaporto exert pressure on liquid 6, to force liquid 6 up the upright tube llinto upper chamber 9, into which the liquid will flow because of a lowervapor pressure in upperchamber 9, due to the cooling by evaporation ofvolatile liquid from The device is now overber 9 and nearabsence ofliquid in lower chamber 8, *and tilts over to the substantiallyhorizontal position represented in Figure i, whereupon the lower end ofupright tube I I is uncovered by the liquid, vapor pressures betweenupperchamber 8 and lower chamber 8 equalize, and liquid 6 news back fromupper to lower chamber, the weight or the liquidtlius returned to lowerchamber 8 again alterin e balance of the device and -causing theidviceto assume the upright position represented inf'igures '1 and 2 As thedevice assumes the substantially hori-' zontal position shown in Figure4, absorbent maliquid tocause operation, as are certain prior artdevices, such as that disclosed in U. 8. Patent 2,240,906. n thecontrary, in the device according to my invention there. is physicalmovement of original, uncondensed liquid, caused by a slight differenceof vapor pressure between upper and lower chambers. A relativelyconsiderable quantity of liquid is thus transferred, resulting inabsolutely reliable operation, due to the considerable weight of suchliquid, instead of the very smallquantity of condensed liquid in priorart devices.

It'will be noted that, in the device according to ourinvention, nodelicate adjustments, or sliding, balancing weights are required, and noknife edges for the support. In fact, no means of bal- I ancing, aftermanufacture, are necessary.

the bottom of lower Although we have shown, by way of example of ourinvention, a device in the shape of a bird on the edge of drinkingfountain, we do not limit ourselves to this particular embodiment, butmay utilize our invention in the form of any rocking or tilting devicedesired, large or smell, or to furnish power to operate other devices,such as movable signs, bells, lights, or even hydrostats or,psychrometers, since we have found that the device according to ourinvention has a period -of operation dependent upon the relativehuterial 8' on upper chamber 9 dips into the water or other-volatileliquid contained in vessel 4, and 'the.supply oi coollngliquid on upperchamber sisrepienished. Y

Our device, according to" our invention, is in no way dependent upondelicate balance, nor in any way dependent upon weight of condensedmidity of the atmosphere at a given temperature.

We claim:

1. A self-contained power unit comprising an evacuated chamber dividedinto lower and upper compartments, said upper compartment having at oneside thereof a horizontally-projecting portion freely communicating withsaid upper compartment, a tube extending from said upper compartment tonear the bottom of said lower compartment, pivot pins attachedvto theside of said lower compartment, the power unit resting upon a support bysaid pivot pins in such manner as to tilt, said lower compartment beingpartly filled with a lowboiling liquid to such extent that when saidpower unitassume's an approximately horizontal position the bottom ofsaid tube is uncovered by said liquid and the said liquid enters saidprojecting portion of said upper compart ment, and means to cool saidupper compartment. 2. A' self-containedpower unit in accordance withclaim 1, in which. the low-boiling liquid is v methylene chloride.

enemas muo'rr snorrr. EDWARD mmrsou'enown, JR.

